DOCSLIB.ORG

Current Challenges in Photoprotection

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Current Challenges in Photoprotection Current challenges in photoprotection HenryW.Lim,MD,a Maria-Ivonne Arellano-Mendoza, MD,b and Fernando Stengel, MDc Detroit, Michigan; Mexico City, Mexico; and Buenos Aires, Argentina Electromagnetic radiation in the ultraviolet, visible, and infrared ranges all produce biologic effects. Ultraviolet filters are the most well-studied photoprotective measure for the adverse effects of ultraviolet radiation. Because of the reported endocrinologic effects of oxybenzone in animal studies, its effects on coral reefs, and its photocontact allergy potential, its use has been minimized in many countries worldwide. New developments in topical antioxidants and oral and subcutaneous agents (eg, Polypodium leucotomos extract, afamelanotide, nicotinamide) with photoprotective and antiphoto- carcinogenic properties could potentially provide addition modalities for protection against the effects of visible light and infrared radiation. ( J Am Acad Dermatol 2017;76:S91-9.) Key words: afamelanotide; antioxidant; nicotinamide; oxybenzone; photoprotection; Polypodium leucotomos extract; sunscreen. lthough the need to prevent acute (ery- thema) and chronic (skin cancer and photo- Abbreviations used: aging) skin damage resulting from exposure 25(OH)D: 25-hydroxyvitamin D A CPD: cyclobutane pyrimidine dimer to ultraviolet (UV) radiation (UVR) (UVB and UVA) is EPP: erythropoietic protoporphyria well understood, the safest and most effective way to FDA: Food and Drug Administration achieve this still presents a number of challenges, MMP: matrix metalloproteinase ROS: reactive oxygen species specifically, in the practical implementation of sun- SPF: sun-protection factor protective measures. These include concerns about UV: ultraviolet the safety of some currently available UV filters, UVR: ultraviolet radiation whether sunscreens detrimentally affect serum vitamin-D levels, whether new nontopical agents can offer significant additional sun protection, and SUNSCREEN SAFETY AND EFFICACY how to protect against recently identified harmful Oxybenzone effects of radiation at frequencies outside the UV Oxybenzone (benzophenone-3) is an organic range of the solar spectrum. filter that absorbs both UVB and short-range UVA It should be emphasized that although sunscreen (UVA2). Because few other organic UVA filters have products are excellent means of photoprotection, been approved by the US Food and Drug they should always be part of the total photo- Administration (FDA), oxybenzone is widely used protection package, which includes seeking shade, in the United States. Concerns were expressed about wearing protective clothing and a wide-brimmed the safety of oxybenzone after reports of cases of hat, and using sunglasses. allergic and photoallergic contact dermatitis and From the Department of Dermatology, Henry Ford Hospital, served as a consultant for La Roche-Posay, Roche, Vichy, and a Detroit ; Department of Dermatology, Hospital General de Pierre Fabre Dermo-Cosmetique/Av ene. b Mexico Dr Eduardo Liceaga ; and Fundacion del Cancer de Accepted for publication September 18, 2016. c Piel, Buenos Aires. Reprint requests: Henry W. Lim, MD, Henry Ford Medical Center, Publication of this supplement is supported by Laboratoires New Center One, 3031 W Grand Blvd, Suite 800, Detroit, MI Dermatologiques Avene. 48202. E-mail: [email protected]. Disclosure: Dr Lim has served as a consultant for Pierre Fabre Published online December 27, 2016. Dermo-Cosmetique/Avene and received research grants from 0190-9622/$36.00 Estee Lauder, Ferndale, and Allergan. Dr Arellano has served as Ó 2016 by the American Academy of Dermatology, Inc. a consultant for Galderma, Bioderma, Sanfer, Pierre Fabre http://dx.doi.org/10.1016/j.jaad.2016.09.040 Dermo-Cosmetique/Av ene, and Leo Pharma. Dr Stengel has S91 S92 Lim, Arellano-Mendoza, and Stengel JAM ACAD DERMATOL MARCH 2017 because of its potential for endocrine disruption andIndianoceans,19 and presenting a hazard to reported in an animal model. Oxybenzone is the the viability of the reefs. most common photoallergen among all the UV Outside the United States oxybenzone has been filters.1 A 10-year retrospective analysis found that replaced in many sunscreens by other UV filters. 70.2% of almost 24,000 patients patch-tested with UV These include broad-spectrum filters such as bemo- filters between 2001 and 2010 had positive reactions trizinol and bisoctrizole, which are not currently to oxybenzone.2 In 2014, oxybenzone was largely available in the United States, and ecamsule, which is responsible for the naming of available in the United States benzophenones as contact only in products approved CAPSULE SUMMARY allergen of the year by the though the New Drug American Contact Dermatitis Application process. In 2015 d In addition to application of sunscreen, Society.3 Potential endocrine the FDA announced that proper photoprotection consists of effects of oxybenzone ecamsule, bemotrizinol, bi- seeking shade, wearing photoprotective were identified in several soctrizole, and 5 other sun- clothing and hat, and using sunglasses. in vitro studies4-6 and an screen ingredients that had in vivo study showed dose- d Ultraviolet filters have been well been awaiting approval in dependent estrogenic activ- established to be effective against the the United States through ity in 21-day-old rats adverse effects of ultraviolet radiation. the Time and Extent fed doses of oxybenzone d With increased understanding of the Application process were 7 ($1500 mg/kg/d). It should effect of visible light and infrared not generally recognized as be noted that the doses of radiation, studies on antioxidants and safe and effective, despite oxybenzone used in the an- oral and subcutaneous topical forms of approval by regulatory imal study were very high photoprotection are ongoing. agencies in many parts of and the estrogenic potency the world.20 detected was 1 million-fold less than the estradiol control.8,9 Short-term studies Antioxidants that looked at topical application of UV filters Traditional sunscreens provide effective protec- including oxybenzone in human beings found that tion against erythema but not similarly effective there were no significant UV filtererelated alter- protection against the generation of reactive oxygen ations on the endocrinologic effects on either repro- species (ROS) in the skin after exposure to UVR, ductive hormones10 or thyroid function.11 especially UVA.21 Therefore, antioxidants are incor- Mathematic modeling indicated that it would take porated in many sunscreen products because of their 277 years using a sunscreen containing 6% oxy- ability to scavenge and reduce levels of ROS, benzone used at 2 mg/cm2 (the dose recommended the primary mediator of oxidative damage to the for sun-protection factor [SPF] testing by the FDA) skin.22-24 Compared with sunscreen alone, the addi- or 1 mg/cm2 (reported real-life use) to achieve the tion of antioxidants has been shown to suppress ROS systemic levels of oxybenzone achieved in the formation by an additional 1.7-fold for SPF 4, and study in rats.12 Oxybenzone has been in use in the 2.4-fold for SPF 15 and 50 formulas, respectively.25 United States since at least the early 1970s with no Sunscreen with added antioxidant has been shown clinical report of estrogenic side effects. Thus, all to be more efficient than sunscreen alone in sup- current data indicate that oxybenzone is safe. pressing other changes in the skin known to be Nonetheless, in the European Union the label of induced to exposure to UVR such as development of a sunscreen containing oxybenzone must include pigmentation, depletion of Langerhans cells, and a cautionary statement (‘‘contains benzophenone- induction of matrix metalloproteinase (MMP)-9.22-24 3’’) if the concentration is over 0.5%.13 These and other data indicate that addition of Oxybenzone has also emerged as a potential antioxidants to sunscreens represents a potentially hazardous environmental contaminant. Water sam- effective strategy to minimize UV damage. The pling studies have shown that it is not fully antioxidants that have been studied include vitamins eliminated during waste water treatment,14,15 and A (retinol), C (ascorbic acid), and E (a-tocopherol), oxybenzone and its metabolites have been and (e)-epigallocatechin-3-gallate, a polyphenol detected in fish, with antiandrogenic and anties- component of green tea. Antioxidants are inherently trogenic effects.16,17 A genotoxic effect of oxy- unstable compounds, however, so are difficult to benzone on coral was recently reported in a formulate in an acceptable, stable, and biologically laboratory study,18 supporting earlier evidence of active composition for sunscreen products. A 2011 bleaching effects on coral in the Atlantic, Pacific, analysis of 12 commercially available US sunscreens JAM ACAD DERMATOL Lim, Arellano-Mendoza, and Stengel S93 VOLUME 76, NUMBER 3 with added antioxidants listed in their labels indi- studies reported low serum 25(OH)D levels associ- cated that 10 had no antioxidant power at all ated with sunscreen application.37-39 However, a (measured as the compound’s capacity to remove a 2009 review of the available evidence concluded certain number of free radicals in certain time that although sunscreens can significantly reduce the 26 intervals) and the other 2 had only low power. production of UVB-induced previtamin D3 when applied under strictly controlled conditions, in real Nanoparticles life, normal use does not generally result in vitamin- The safety of sunscreens containing inorganic
Load more

Recommended publications
  • GAO-18-61, SUNSCREEN: FDA Reviewed Applications For
    United States Government Accountability Office Report to Congressional Committees November 2017 SUNSCREEN FDA Reviewed Applications for Additional Active Ingredients and Determined More Data Needed GAO-18-61 November 2017 SUNSCREEN FDA Reviewed Applications for Additional Active Ingredients and Determined More Data Needed Highlights of GAO-18-61, a report to congressional committees Why GAO Did This Study What GAO Found Using sunscreen as directed with other The Food and Drug Administration (FDA), within the Department of Health and sun protective measures may help Human Services, implemented requirements for reviewing applications for reduce the risk of skin cancer—the sunscreen active ingredients within time frames set by the Sunscreen Innovation most common form of cancer in the Act, which was enacted in November 2014. For example, the agency issued a United States. In the United States, guidance document on safety and effectiveness testing in November 2016. sunscreen is considered an over-the- counter drug, which is a drug available As of August 2017, all applications for sunscreen active ingredients remain to consumers without a prescription. pending after the agency determined more safety and effectiveness data are Some sunscreen active ingredients not needed. By February 2015, FDA completed its initial review of the safety and currently marketed in the United States effectiveness data for each of the eight pending applications, as required by the have been available in products in act. FDA concluded that additional data are needed to determine that the other countries for more than a ingredients are generally recognized as safe and effective (GRASE), which is decade. Companies that manufacture needed so that products using the ingredients can subsequently be marketed in some of these ingredients have sought the United States without FDA’s premarket approval.
    [Show full text]
  • Table 1 - Experimental and Predicted Physical-Chemical Parameters of the Most Recently Investigated UV-Absorbers
    Table 1 - Experimental and predicted physical-chemical parameters of the most recently investigated UV-absorbers. INCI name (INN/XAN) Chemical structure Brand name Absorption Molecula LogP Water solubility Melting spectrum range r weight (mg/L) point (°C) (g/mol)4 diethylamino Uvinul® A Plus UVA1 5.7-6.21 <0.01 (20°C) 1 54; 314 hydroxybenzoyl hexyl 397.515 (dec.) 1 benzoate Butyl Eusolex® 9020, UVA 310.393 4.514 2.2 (25°C)4 83.54 methoxydibenzoylmetha Parsol® 1789 ne (avobenzone) 4-methylbenzylidene Eusolex® 6300 UVB 258.397 4.95 1.3 (20°C) 66–68 camphor (enzacamene) Parsol® 5000 Uvinul® MBC 95 Octocrylene Eusolex® OCR, UVB 361.485 6.783 0.00383 N/A (octocrilene) Parsol® 340, Uvinul® N539T, NeoHeliopan® 303 USP isoamyl p- Neo Heliopan® UVB 248.322 3.61 4.9 (25°C)1 N/A methoxycinnamate E1000 (amiloxate) Ethylhexyl triazone Uvinul® T150 UVB 823.092 > 7(20 °C) 6 < 0.001 (20.0 °C) 6 1296 Ethylhexyl Parsol® MCX, UVB 290.403 6.14 0.041 (24 °C and N/A methoxycinnamate Heliopan® New pH 7.1) 4 (octinoxate) Ethylhexyl dimethyl Escalol™ 507 UVB 277.4084 5.774 0.54 (25 °C) 4 N/A PABA (padimate-O) Arlatone 507 Eusolex 6007 benzophenone-3 Eusolex® 4360 UVA2+ UVB 228.247 3.72 3.7 (20°C) 2 62-652 (oxybenzone) bis-ethylhexyloxyphenol Tinosorb® S UVA1+UVB 627.826 12.61 <10-4 80.401 methoxyphenol triazine (bemotrizinol) Phenylbenzimidazole Eusolex® 232 UVA2+ UVB 274.2945 -1.1 (pH 5) > 30% (As sodium N/A sulfonic acid Parsol® HS -2.1 (pH 8)5 or (ensulizole) Neo Heliopan® triethanolammoniu Hydro m salt at 20°C) 5 1 (3) 2 (34) 3 (44) 4 Pubchem 5 SCCP/1056/06 Opinion on phenylbenzimidazole sulfonic acid and its salts 6 BASF safety data sheet Table 2 – In vitro studies for the assessment of skin permeation/penetration of sunscreens.
    [Show full text]
  • Photophysics and Skin Penetration of Active Agents in a Commercial Sunscreen and Insect Repellent
    PHOTOPHYSICS AND SKIN PENETRATION OF ACTIVE AGENTS IN A COMMERCIAL SUNSCREEN AND INSECT REPELLENT by DONALD PRETTYPAUL A Dissertation submitted to the Graduate School-Newark Rutgers, The State University of New Jersey In partial fulfillment of the requirements for the degree of Doctor of Philosophy Graduate Program in Chemistry written under the direction of Professor Richard Mendelsohn Professor Piotr Piotrowiak and approved by Newark, New Jersey October 2018 ©2018 Donald Prettypaul ALL RIGHTS RESERVED ABSTRACT OF DISSERTATION PHOTOPHYSICS AND SKIN PENETRATION OF ACTIVE AGENTS IN A COMMERCIAL SUNSCREEN AND INSECT REPELLENT By DONALD PRETTYPAUL Dissertation co-Directors: Professor Richard Mendelsohn Professor Piotr Piotrowiak This dissertation is focused on active agents in commercial sunscreen and insect repellent products. It consists of two parts, the first focusing on the photophysics of a sunscreen active agent and the second on the permeation and spatial distribution of the sunscreen active and an insect repellent active when these agents are applied to ex-vivo human skin. In the photochemistry study, ultrafast spectroscopy was used to study the excited state dynamics of the sunscreen molecule, Bemotrizinol. The work focused on the dissipation rates of the electronic excitation energy in different solvents. To complement the results from time-resolved femtosecond spectroscopy, Hartree- Fock UH/UHF 6-31G* calculations were used to characterize the ground and excited states potential energy surfaces. The results indicate that the excited state deactivation pathway follows a proton coupled electron transfer process which ii proceeds via a concerted mechanism. The dependencies on solvent polarity, viscosity, and H/D isotope effects, were investigated. Sunscreen products have been developed to protect skin from ultraviolet (UV) radiation; to achieve adequate protection, the sunscreen must be evenly applied and remain on the surface of the skin.
    [Show full text]
  • New Technology Provides Cosmetically Elegant Photoprotection Zoe Diana Draelos, MD; Christian Oresajo; Margarita Yatskayer; Angelike Galdi; Isabelle Hansenne
    COSMETIC CONSULTATION New Technology Provides Cosmetically Elegant Photoprotection Zoe Diana Draelos, MD; Christian Oresajo; Margarita Yatskayer; Angelike Galdi; Isabelle Hansenne he primary preventable cause of photoaging is United States, as there is no official rating system for exposure to UVA radiation. This wavelength UVA photoprotection yet. T emitted by the sun is present year round in all Ecamsule absorbs UVA radiation in the range of 320 to latitudes. Currently, the majority of sun-protective prod- 360 nm, but its peak absorbance occurs at 345 nm. It is ucts provide excellent UVB protection with minimal UVA typically combined with other organic sunscreen ingredi- protection. Although UVB protection is important in ents, such as avobenzone and octocrylene. Avobenzone, order to prevent sun damage to the skin from occurring, which is a photounstable photoprotectant, becomes UVA protection is equally important. New developments photostable when combined with octocrylene. These in raw material science have led to the manufacture of ingredients yield a photostable broad-spectrum sunscreen novel ingredients able to provide unprecedented photo- combination. However, the active sunscreen agents are protection COSin the UVA spectrum. DERMonly part of the formulation. Also important in sunscreen One of the most significant developments in cutaneous is the construction of the vehicle to deliver the photo- UVA protection was the discovery of ecamsule (Figure 1), protectants in an aesthetically pleasing manner, enticing also known as Mexoryl SX. Mexoryl SX, which has patients to wear the product. Sunscreens fail to be effec- the International Nomenclature of Cosmetic Ingredients tive if they remain in the bottle. name of terephthalylidene dicamphor sulfonic acid, is In order to evaluate the efficacy and tolerability of a water soluble.
    [Show full text]
  • WO 2013/036901 A2 14 March 2013 (14.03.2013) P O P C T
    (12) INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) (19) World Intellectual Property Organization International Bureau (10) International Publication Number (43) International Publication Date WO 2013/036901 A2 14 March 2013 (14.03.2013) P O P C T (51) International Patent Classification: (81) Designated States (unless otherwise indicated, for every A61K 8/30 (2006.01) kind of national protection available): AE, AG, AL, AM, AO, AT, AU, AZ, BA, BB, BG, BH, BN, BR, BW, BY, (21) International Application Number: BZ, CA, CH, CL, CN, CO, CR, CU, CZ, DE, DK, DM, PCT/US2012/054376 DO, DZ, EC, EE, EG, ES, FI, GB, GD, GE, GH, GM, GT, (22) International Filing Date: HN, HR, HU, ID, IL, IN, IS, JP, KE, KG, KM, KN, KP, 10 September 2012 (10.09.2012) KR, KZ, LA, LC, LK, LR, LS, LT, LU, LY, MA, MD, ME, MG, MK, MN, MW, MX, MY, MZ, NA, NG, NI, (25) Filing Language: English NO, NZ, OM, PA, PE, PG, PH, PL, PT, QA, RO, RS, RU, (26) Publication Language: English RW, SC, SD, SE, SG, SK, SL, SM, ST, SV, SY, TH, TJ, TM, TN, TR, TT, TZ, UA, UG, US, UZ, VC, VN, ZA, (30) Priority Data: ZM, ZW. 61/532,701 9 September 201 1 (09.09.201 1) US (84) Designated States (unless otherwise indicated, for every (71) Applicant (for all designated States except US): UNIVER¬ kind of regional protection available): ARIPO (BW, GH, SITY OF FLORIDA RESEARCH FOUNDATION, GM, KE, LR, LS, MW, MZ, NA, RW, SD, SL, SZ, TZ, INC.
    [Show full text]
  • Annex VI, Last Update: 02/08/2021
    File creation date: 03/10/2021 Annex VI, Last update: 22/09/2021 LIST OF UV FILTERS ALLOWED IN COSMETIC PRODUCTS Substance identification Conditions Wording of Reference Maximum conditions of Product Type, concentration Update date number Chemical name / INN / XAN Name of Common Ingredients Glossary CAS Number EC Number Other use and body parts in ready for use warnings preparation 2 N,N,N-Trimethyl-4-(2-oxoborn-3-ylidenemethyl CAMPHOR BENZALKONIUM 52793-97-2 258-190-8 6% 15/10/2010 ) anilinium methyl sulphate METHOSULFATE 3 Benzoic acid, 2-hydroxy-, HOMOSALATE 118-56-9 204-260-8 10% 02/08/2021 3,3,5-trimethylcyclohexyl ester / Homosalate 4 2-Hydroxy-4-methoxybenzophenone / BENZOPHENONE-3 131-57-7 205-031-5 6% Reg (EU) Not more than Contains 02/08/2021 Oxybenzone 2017/238 of 10 0,5 % to protect Benzophenone-3 February 2017- product (1) date of formulation application from September 2017 6 2-Phenylbenzimidazole-5-sulphonic acid and its PHENYLBENZIMIDAZOLE SULFONIC 27503-81-7 248-502-0 8%(as acid) 08/03/2011 potassium, sodium and triethanolamine salts / ACID Ensulizole 7 3,3'-(1,4-Phenylenedimethylene) bis TEREPHTHALYLIDENE DICAMPHOR 92761-26-7 / 410-960-6 / - 10%(as acid) 26/10/2010 (7,7-dimethyl-2-oxobicyclo-[2.2.1] SULFONIC ACID 90457-82-2 hept-1-ylmethanesulfonic acid) and its salts / Ecamsule 8 1-(4-tert-Butylphenyl)-3-(4-methoxyphenyl) BUTYL 70356-09-1 274-581-6 5% 15/10/2010 propane-1,3-dione / Avobenzone METHOXYDIBENZOYLMETHANE 9 alpha-(2-Oxoborn-3-ylidene)toluene-4-sulphoni BENZYLIDENE CAMPHOR SULFONIC 56039-58-8 - 6%(as acid)
    [Show full text]
  • Cutaneous Permeation and Penetration of Sunscreens: Formulation Strategies and in Vitro Methods
    cosmetics Review Cutaneous Permeation and Penetration of Sunscreens: Formulation Strategies and In Vitro Methods Silvia Tampucci * ID , Susi Burgalassi ID , Patrizia Chetoni ID and Daniela Monti ID Department of Pharmacy, University of Pisa, 56126 Pisa, Italy; [email protected] (S.B.); [email protected] (P.C.); [email protected] (D.M.) * Correspondence: [email protected] Received: 1 November 2017; Accepted: 7 December 2017; Published: 25 December 2017 Abstract: Sunscreens are the most common products used for skin protection against the harmful effects of ultraviolet radiation. However, as frequent application is recommended, the use of large amount of sunscreens could reflect in possible systemic absorption and since these preparations are often applied on large skin areas, even low penetration rates can cause a significant amount of sunscreen to enter the body. An ideal sunscreen should have a high substantivity and should neither penetrate the viable epidermis, the dermis and the systemic circulation, nor in hair follicle. The research of methods to assess the degree of penetration of solar filters into the skin is nowadays even more important than in the past, due to the widespread use of nanomaterials and the new discoveries in cosmetic formulation technology. In the present paper, different in vitro studies, published in the last five years, have been reviewed, in order to focus the attention on the different methodological approaches employed to effectively assess the skin permeation and retention of sunscreens. Keywords: sunscreens; formulation; in vitro methods; cutaneous permeation; skin penetration 1. Introduction The detrimental effects of human exposure to ultraviolet (UV) radiation have been widely investigated and can be immediate, as in the case of sunburns, or long-term, causing, in most cases, the formation of oxidizing species responsible of photo-aging, immunosuppression and chronic effects such as photo carcinogenicity [1,2].
    [Show full text]
  • Sun Protection
    DRUG NEWS Recommending the Best Sun Protection Clinical Pearls: o Recommend a “broad-spectrum” sunscreen – one that covers UVB, UVA1, and UVA2. o Recommend SPF 30-50 o Advise on non-pharmacological sun protection methods o Emphasize proper sunscreen application technique o Emphasize skin protection when taking drugs known to cause photosensitivity. Familiarize yourself with known implicated drugs by referring to appendix 2. Background 1-4 The sun emits 3 types of ultraviolet (UV) radiation: UVC (100-290 nm), UVB (290-320 nm), and UVA (320 -400 nm). UVA rays can be further divided into the shorter UVA2 rays and the longer UVA1 rays. UVC rays, the shortest rays, are completely absorbed by the ozone layer, whereas UVB rays penetrate the epidermis and UVA rays, the longest rays, penetrate into the dermis. The main consequence of UVB irradiation is sunburn, but can also include immunosuppression and skin cancer. Consequences of UVA radiation include: phototoxicity (i.e. involvement in drug-induced sun sensitivity reactions), photo-aging, immunosuppression, and skin cancer. What is SPF? 2,5,6,7 It is easy to be misled by Sun Protection Factors (SPF). SPF is assessed through a standardized test by finding the ratio of the minimal dose of solar radiation that produces perceptible erythema (i.e., minimal erythema dose) on sunscreen-protected skin compared with unprotected skin. Sunburn is caused primarily by UVB rays (and shorter UVA2 rays), and thus SPF indicates mostly UVB protection. However, UVA protection is equally important since it is responsible for photo-aging and cancer. Therefore, it is important to look for the phrase “broad spectrum” when choosing a sunscreen as broad spectrum indicates both UVB and UVA protection.
    [Show full text]
  • Four Common Sunscreen Questions – Spring 2015
    Four common sunscreen questions – Spring 2015 Use this information SPF to help you advise 30 your customers about Use the Sun Protection System sunscreen use. 30 SP F 1. How do sunscreens filter the slip, slop, slap, and wrap sun’s rays? Sunscreens may contain physical or chemical Ethoxyethyl p-methoxycinnamate barriers to screen skin against the sun’s (cinoxate)) ultraviolet radiation (UV radiation). While physical barriers reflect or scatter the UV rays, » Salicylates (Homomenthyl salicylate chemical barriers act by absorbing the UV (homosalate), Ethylhexyl salicylate (octyl radiation before it hits the skin. salicylate/octisalate), Trolamine salicylate General advice is to choose a sunscreen which » Avobenzone (butyl methoxydibenzoylmethane) is broad spectrum, which means it filters both UVA and UVB rays. Those who have sensitive » Ecamsule ((terephthalylidene dicamphor skin should choose a sunscreen labelled sulfonic acid; Mexoryl SX) hypoallergenic or low irritant. » Ensulizole ((phenylbenzimidazole sulfonic Typical chemical absorbers include: acid) » Aminobenzoic acid derivatives (Glyceryl » Bemotrizinol (Tinosorb S) PABA), Padimate O, Roxadimate) » Bisoctrizole (Tinosorb M) » (Dioxybenzone, Benzophenones Physical blockers are titanium dioxide and Oxybenzone, Sulisonbenzone) zinc oxide. When applied they leave a thick » Cinnamates (Octocrylene, Octyl opaque (white) layer on the skin. Microfine or methoxycinnamate (octinoxate), nanoparticles of both are transparent on the skin and reflect UV radiation. 2. Do babies’ need a special sunscreen? » Babies’ skin is very sensitive and can sunburn easily so keep them out of the sun. » Once a baby is moving use the sun protection system. » Patch test an untried sunscreen on the skin 24 hours before applying it widely to check that there is no reaction.
    [Show full text]
  • Sunscreen: the Burning Facts
    United States Air and Radiation EPA 430-F-06-013 Environmental Protection (6205J) September 2006 1EPA Agency Sun The Burning Facts Although the sun is necessary for life, too much sun exposure can lead to adverse health effects, including skin cancer. More than 1 million people in the United States are diagnosed with skin cancer each year, making it the most common form of cancer in the country, but screen: it is largely preventable through a broad sun protection program. It is estimated that 90 percent of non- melanoma skin cancers and 65 percent of melanoma skin cancers are associated with exposure to ultraviolet 1 (UV) radiation from the sun. By themselves, sunscreens might not be effective in pro­ tecting you from the most dangerous forms of skin can- cer. However, sunscreen use is an important part of your sun protection program. Used properly, certain sun­ screens help protect human skin from some of the sun’s damaging UV radiation. But according to recent surveys, most people are confused about the proper use and 2 effectiveness of sunscreens. The purpose of this fact sheet is to educate you about sunscreens and other important sun protection measures so that you can pro­ tect yourself from the sun’s damaging rays. 2Recycled/Recyclable—Printed with Vegetable Oil Based Inks on 100% Postconsumer, Process Chlorine Free Recycled Paper How Does UV Radiation Affect My Skin? What Are the Risks? UVradiation, a known carcinogen, can have a number of harmful effects on the skin. The two types of UV radiation that can affect the skin—UVA and UVB—have both been linked to skin cancer and a weakening of the immune system.
    [Show full text]
  • UVA Chemical Filters
    UVA Chemical Filters: A Systematic Study Jacqueline F. Cawthray, B. Science (Hons) A thesis submitted for the degree of Doctor of Philosophy in The University of Adelaide Department of Chemistry February 2009 Chapter 1 1 Introduction Sunlight, incorporating ultraviolet radiation, provides the energy necessary to sustain life. Ultraviolet radiation (UVR) is the non-visible part of the solar spectrum incorporating the wavelengths between 100 and 400 nm. Wavelengths in the ultraviolet region of the spectrum are further subdivided into UVA, UVB and UVC. The physiological responses to UVR can be both beneficial and harmful. Small doses of UV are required to produce vitamin D and in some cases therapeutic improvements are observed for skin disorders. However, long and short-term exposure can cause a variety of detrimental biological effects in humans. The biological effects of UVB have been intensively researched and are largely well understood. Armed with this knowledge, public attitudes have changed accordingly. The bronzed Aussie is no longer the national icon he or she once was, as the use of sun protection methods, including sunscreens, has now become common practice. Until recently, UVA was believed to play little or no role in the damaging effects of UVR and was often neglected in studies. However, there is now accumulating evidence that UVA plays a major role in sunlight-induced damage. As information regarding the detrimental effects of UVA increases, there needs to be an accompanying increase in public awareness regarding the potential hazards and the need for sunscreen filters that protect skin from UVA wavelengths has become a current issue of importance.
    [Show full text]
  • Photoprotection: a Public Awareness
    Internet Journal of Medical Update, Vol 3, No. 1, Jan-Jun 2008 Letter to editor Photoprotection: a public awareness Dr. (Ms.) Meera Sridhar MD, DVD, DDV Consultant Dermatologist, Dubai, United Arab Emirates Sir, earth on a particular day and is a recognized part of the weather report in many countries. Excessive solar ultraviolet radiation exposure of the skin has been associated with several FACTORS AFFECTING THE AMOUNT skin disorders/diseases including premature OF ULTRAVIOLET RADIATIONS aging of the skin and skin cancers. Avoiding REACHING THE EARTH’S SURFACE exposure to sun is the best method but AT A PARTICULAR TIME AND PLACE impractical. Public is informed through UV ARE DEPENDENT ON: Index of the amount of harmful ultraviolet rays 1. Time of the day: Two third of the total reaching the earth and choosing of the right UVR reaches the earth between 10 am and SPF (Sun Protection Factor) is the practical 2 pm of which 10 % is UVB and 90 % and effective approach for photoprotection. UVA. Increasing pollution levels (release of 2. Surface reflection: chlorofluoro carbon compounds) into the Snow and ice reflect 80 % of UVR atmosphere over the last 20 years has resulted Sand reflects 20 % of UVR in gradual depletion of the ozone layer which Most ground surfaces reflect < 10 % in turn has resulted in greater amounts of UV of UVR radiations of the sun reaching the earth’s Water reduces penetration of UVR by surface as also global warming. The sun rays 50 % have been broadly classified into 3 groups 3. Seasonal: Maximum radiation occurs based on the wavelength of the electro during summer and minimal in winter.
    [Show full text]